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From: Robert A Duff <bobduff@world.std.com>
Subject: Re: Problem trying to implement generics.
Sender: bobduff@world.std.com (Robert A Duff)
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Date: Sat, 14 Apr 2001 01:33:16 GMT
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Date: 2001-04-14T01:33:16+00:00
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Brian Rogoff <bpr@shell5.ba.best.com> writes:

> Or, would you just allow procedures to return values? ;-)

Yeah.  ;-)

> Did anyone see this during the Ada 95 design? I thought J.P. Rosen (who
> showed most of us this evil trick :) said something about having noticed
> it early but never actually implementing it until later. I'm sure I'm
> botching the story: J.P, what's the history here?

I think I discovered it independently of J.P. Rosen, sometime *after*
the Ada 95 standard.  I wrote in AARM-7.5(1.a):

        1.a   Discussion:  The concept of the value of a limited type is
        difficult to define, since the abstract value of a limited type often
        extends beyond its physical representation.  In some sense, values of
        a limited type cannot be divorced from their object.  The value IS
        the object.

Or maybe Tucker wrote that.  I don't really remember, since we traded
off writing assignments so often, and we were in tune with each other's
thinking.  Anyway, I don't think I realized the full ramifications of
"the value IS the object" until after the 9X design was over.

- Bob